Universal mandrel



June 1s, 1925. 2 1 1,542,128

J. HAUSHALTER NIVERSAL MANDREL Filed Oct. 22, 1921 YW Integra/r. f

Patented June 16, 1925.

PATENT rricE.

JOHN Hausfrauen, or MILWAUKEE, Wrsconsnv.

UNIVERSAL Marianen j application' inea october 22,1921. serieu uo. seaere.

To all whom t may concern.'

" Be it known that I, rlor-1N -l-lausr-rnifrnn, a citizen of the United States, residing at Milwaukee, county of Milwaukee, and State of Vlisconsin, have invented new and useful ln'iprovements in Universal Mandrels', of `which the following is a specification. i

This invention relates to a universal mandrel which, although of `wide applicability',

is particularly suited to dental work.

Objects of this invention are to provide an apparatus which will facilitate the grinding of angularly arranged surfaces, particularly when located in relatively diflicultly accessible places; which is adapted to receive and use grinding or polishing disks, wheels and similar members, of the usual or conventional style; and which will permit the ready and easy changing or replacing of such members. Further objects are to provide a dental mandrel with a readily removable disk holding shaft, with manually operable means for normally retaining such shaftrin operative position, and to provide such a device of sturdy and simple construction, and' one which may be cheaply and rapidly produced.

An embodiment of the invention is shown in the accompanying drawings, in which- Figure 1 is a view of the mandrel show-` ing one of the positions it assumes in use,- the teeth being indicated in dotted lines.

Figure 2 is a sectional viewcorresponding to Figure 1.

Figure 3 is a view of the removable spindle detachable from the apparatus. 1

Figure f1 is a similar view of the sheath or support for the removable spindle.

The device comprises a conically shaped member 1 which serves as a handle and also `as a sheath for the terminal portion of the fiexible shaft of the dental engine. This member or body portion 1 is hollow thruout its major portion, and at lits forward end is provided with a solid or heavier portion 2 which forms a bearing for the driving shaft 3, such latter shaft being adapted for operative connectionto the flexible shaft. This driving shaft is provided with a rigidly attached collar 1 which seats in a recessed portion at the outer end of .the member 1. It is prevented from passing outwardly from Vsuch member by means of the face 5 of the bearing or support 6, for the removable spindle 7. This support has a threaded portion 7 which engages the internal threads ofthe recess S at the outer end of the member 1. It is screwed into such member until its shoulder 9 contacts with the corresponding outer shoulder of the member 1, and prevents further inward motion. When positioned, there is a slight play allowed the collar 4E so that the shaft 3 Vmay freely rotate in its operative or retained position.

The removable spindle 7 is similarly provided with a rigidly attached collar 10 which contacts on one face with the outer face 11 of the supporting member 6. A detent or hinged curved clip 12 is pivotally mounted at 13 to the member 6 and has an inwardly projecting lip 14 which engages the outer face of the collar 10, and thereby `serves to retain such removable shaft or spindle in operative position. This clip is resiliently held in the positionshown in the drawings, by means of a relatively light spring 15 riveted at 16 to the `inner or free end 17 of the clip, the other end of the spring 15 slidably` engaging a portion of the member 6. It will be seen that when it is desired to remove the shaft 7, the free end 17 of the clip 12 may be depressed,

Vthereby elevating the lip 14 and allowing the 'collar 10 to pass outwardly, permitting the removal of the shaft 7.V The spindle or shaft 7 is provided with a terminal collar` or enlarged portion 18 which is adapted to receive the threaded stem of a screw 19, to thereby allow a grinding or polishing disk or wheel 2() to be clamped in operative position.

It is to be noted that the members 1 and 6 are angularly related to-each other, and

`to accommodate this angular arrangement and allow operative driving from the shaft 3 to the shaft 7, a universal joint 21 is formed between the shafts 3 and 7. This joint 21 is produced by providing a series of tapered relatively pointed teeth 22, (see figures 2 and 3) upon both the shafts 3 and 7, so that such teeth may freely mesh and allow sliding motion to occur between them so that operative driving connection is maintained between the shafts 3 and 7, altho the angular relation exists.

The device lends itself readily to a great number of uses, one of which is indicated in Figure 1. It will be seen from such figure that when it is desired to polish the downwardly and rearwardly slanting face 23 of a tooth 24E, it is merely necessary to insert the device into the mouth of the patientr with the major aXis of such device substantially horizontal, as shown. Under these conditions the necessary angular position of the grinding or polishing element 20 is secured so that the otherwise diliicultly accessible face 23 may be readily ground or polished.

It is obvious from an inspection of such ligure that the angular relation of the forward and rear portions of the device admirabl,1 adapts it to this opera-tion, and allows the angular face to be ground as far down as it may be desired Without binding, and without damage to adjacent teeth. Also it will be seen that by rotating the device about its major axis the grinding element may bo positioned in any desired plane, either verti cally or angularly disposed upon either side of the vertical axis.

It will be seen that the spindle 2, which is subject tol constant jarring and wear, may be readily removed and replaced Without disturbing other portions of the apparatus, and that the grinding elements may be as readily interchanged.

I claim l. A dental mandrel comp-rising a bodyportin hav-ing two. angularly related parts, a driving shaft having a bearing in one of said parts, a driven shaft having a beamingv .in the other of said parts and replaceably mounted therein, said shafts vbeing formed at their ends to provide a quickly detachable driving connection whereby said second shaft may be rotated by the first shaftA when properly positioned in operative relation thereto, and releasable means wholly exterior to said body portion for maintaining said second shaft in operative power1 receiving position with respect to the first shaft, said releasable means being adapted to permit the bodily removal of the second shaft.

A dental mandrel including a tool pro-. vided with bearings for tivo angularly re.- lated shafts, a driving shaft rotatably mountedin one of said bearings, a driven shaft rotatably mounted in another of 'said bearings and axially removable therefrom, means wholly exterior to said body portion for maintaining said driven shaft operatively positioned within its bearing, and power transmitting means adapted in the operative position of the driven shaft to effect the rotation of said shaft from the driving shaft while permitting the ready removal of the driven shaft from its bearing, said power transmitting means including teeth formed upon thel related ends of each of said shafts.

3. A dental mandrel comprising having bea' O's for two angularly related shafts, a dri ng shaft mounted in one of said bearings and provided with axially projecting teeth upon its inner end, a driven shaft removably associated with a second bearing and pr vided with teeth adapted to meshA with the teeth upon the driving shaft, a collar upon the driven shaft exterior to its bearing, and a latch movably associated with said body and engageable with the exterior portion of said collar whereby said driven shaft may be removably retained with its teeth in operative association with the teeth of the driving shaft.

4. In a device of the character described the combination with a handle provided with internal bearings having their axes at an obtuse angle, of a. driving shaft mounted in one of said bearings and provided at its end with tee-th Wholly within the diameter of said bearing, a driven shaft in the other of said bearings and provided with teeth to mesh with the driving shaft and wholly within the diameter of its bearing, said driven shaft and the teeth thereof being bodily removable axially from said bearing, a shoulder on said driven shaft etc teriorly of said bearing, and a retaining device mount-ed on said handle and adapted forreleasable engagement about said shoul-v der whereby to maintain said driven shaft in said bearing with its teeth in mesh with those ofthe driving shaft.

a body 

